You could look into the " Beale woodley " meter( basically a $5 multimeter) , I used to use one , or what the facette gemmaster 2 use , a strain gauge ( $400) . If you look into them they might give you ideas . You probably know about these, if not , might help with your overall design , I am not an engineer :)but these are both usefull for depth of cut as a " soft stop " the delay when to stop cutting could cause problems , yet could be set sooner . As opposed to a hard stop , seems as it might be more usefull to your aplication .

Hmm ok, thats for the pressure but that is for later if i have the digital & mechanical part is done. But the idea is clear thnx :- )

But i cant inmagine that the overall faceting machine is going under the .05 with the accuracy or would all the parts they use on there machines all be precission parts? It just cant. For example i should buy two new bearings for my cutting head rotation, im not going to buy new ones beqourse i clean them and test them first for backlash. But they cost around 300 euro's each so thats already around 840 UAD for a pair of them only a simpel bearing. It has a error About a few micron but who cares :- ) but a bearing of a few austrailian dollars can never reatch the precission from the 300 euro's one!

But oke maybey i want too mutch lets do so:

Im building up my machine with the understanding that i reatch an accuracy of 0.1 mm. then i have done a greath job! I hope!

Everything else under the 0.1 mm is a gift.

Is that a better idea? I just continue with the thing i do and try my best for getting under the 0.1 but my goal Will be 0.1 in accuracy.

What I meant with 0.1 degree is that when I set the angle, I can hardly tell if I do 43.25 or 43.35, but when I cut the other facets, they will be at the same angle at the first one +- 0.02 degree, I just do not know what is the exact value of the angle, but all the facets need to be cut at the same depth, and the dial gauge allows me to reach that +-0.02 precision (I am just not sure of the absolute value of the angle - and I don't care, reapetability is the key).

In terms of mm, it is easy to calculate, the distance between the pivot and the stone is about 15cm, so you can calculate what a angle of 0.01degree means in term of displacement at the end of the 15cm arm (I am lazy I let you do the maths).

That is what i want to know! The machine accuracy! That is unknown, the manufactor can say it is 0.1 or 0.01 mm in accuracy but i know with the used parts te normal lapidary can not be that accurate.

So thats why im going for at least for the machine accuracy of 0.1 mm. My reapetability is verry high precise, lower than 0.01 mm. Also that one would i take on 0.1 mm every thing lower then that would be great!

So my angel setting would theoretical be 0.006 degrees. Lets say it would also be 0.1 deg in accuracy. Then my mission would be accomplished! I just wanted to know what i need to do to get my machine even in accuracy as a standard lapidary

Sorry for the difficult question i have been asking. I thougth it is just too important to ask.

I have a simple task/test for you all, just out of curiosity. You dont have to do it but im verry curiosity! Take a cheap stone and just make a girdle on it on 90 deg. But Set your machine so that you get a girdle of 5 mm (Machine Settings! As you always do!) if you are done measure the girdle with an digital caliper and tell me what diameter on the caliper is! If your machine is in inches then take 0.2 inch for the girdle! Take a picture of your measurement and post it here Im just So curios about the results!

Nice Kingsolomon! That meens that everything is around an accuracy of 0.01 mm! And if i may ask how mutch this machine costs?! (Ultra Tec). I hope i can reach the 0.01. I hope :- ) What is the runout from your cutting head? Dit you measure that?

Wow this whole thread is written in chinese.. i cannot understand any of it but still interesting lol

I should have a better grasp off all the terminology than I do. I just know how to operate one. Might need to engage in some study. Though you don't need to understand all the big words to be able to cut good stones, the more you do the better.

Hmm there are more people that are looking in this thread then i tougth! hehehe. Oke that was all about the accuracy! It's time to build witch i can not do yet... first i need to have some parts like my second set of linear guides. And i have to order 3 sets of spindle bearing blocks probably in China... (i dont like China stuff... it always breaks in my hands ) Also need to look for a tooling plate... An aluminium plate that has an accuration of +/- 5/1000th of a milimeter... but they are also a bit expensive, i need one for my first turning table. (for the Zr axis). Otherwise i need to flatten it by a another company or so. Becourse i cant flattening by a thousands. So a tooling plate wil be perfect! 400x400x20 mm in size. The baseplate wil be 360 x 240 x 20 mm.

Buyed 3 more ball screw spindles for my machine! Small ones but there fine one of them i can use for the spatter chamber or how you call it. I will make a drawing of the base plate and post it. When i got the plate aluminium then i will first cut it in wood for test, if the test on wood is oke i will mill it in aluminium. 20mm is a thick plate and dont want to destroy that large plate.

I thougth about it to make to complete machine out of tooling plates. But the price...

I can tell you about the weigth of the machine, but i thougth i already told ya 150kg. Next week i have the house by myself my wife and my daughter are going to her parents and then i got some time to draw the baseplate

I also thougth about the cuttinghead unit, i think im going to make it all by myself, i having some problems to set it on my horizontal shaft. And i also see some problems with the motor mountings.

The second pair of Linear Guides has arived! 35mm, got some problems with quick rost, the one where i buyed these from had them in the barn... a wooden barn... have clean them all 3 and set them in the oil. All guide cars cleaned and... i dont know what it is but im missing 1 steel ball... But that doesnt have any influence for my machine! I have a normal tin (like a red bull tin) on one of the guide cars so you can see there huge! I think i just need one car for the X (at both sides) and also for the Y shaft. One guide rail is defect... Some one put over the 20 Tons on the machine because there are steel ball marks on the rail... in the middle... But ill cut the rail in two and use only half of it.

One more photo, i have put all on the ground, now i can take a look for making my machine base. This is about the base in its total, the rest wil be build upon the rotary table. I hope it will work I took one car off, because i dont have my chrome steel balls yet! Weight 100Kg+

Do have a better plan for building up the robot! By turning the rotary table upside down, with motor up. So that i can start from the ground, thus dont need to use the feets. And i can build it all compacter & less problems with setting up the accuracy. I'f made a photo, but you need to have a bit fantasy to see what i meaning, whats is on the table shoult stand straigth up. These are only the big parts. And not even all parts from the facetting robot but its a setup.

Also the motor you see in the middle is a 3 Newton meter motor but it will be a 8.4Nm or a 12Nm. The linear guide is holding rotor 2 for the facetting arm. At this way i have more play with the machine.

The parts you see, are for horizontal turning, vertical turning and lifting the vertical turntable up to about 100 - 200 mm. Weight 50Kg? if its done.

Took the linear guides apart otherwise im breaking the glass And i need to chop a piece off the linear guides

My bearing holders arent yet done but hopefully they come this week! Also received all of my end supports for the spindles! Yeah! without paying customs this time! The last time i paid 56 euro's for customs...

I have tried to test my NSK bearings for my rotating axis Zr and Yr im glad with the results!

Testing NSK Super Precision Angular Bearings

I could measure about 3 micron but need to test it at a another way. Ill hope i get a new dail indicator (puppy dial indicator) but couldnt find a good and a affordable one. Also in this testing every movement gives problems on the dail indicator...

Yes! My bearing houses/holders have arived! Now i should be able to build every thing up!? I hope! First i need to drill some holes on the top. This should be done with the cnc, its a bit tricky to fasten it on my bed. But ill give it a try!

The 2 small ones wont be used for the faceting machine, one im going to use as a 4th axis and the other, uhm dont know yet but the big ones are almost the same as the small ones. I only put the bearings in it and the harmonic drive.

Hmmzz, Made my first drawing for the first rotor... Im not shure im going to place the spindle on the first table. At this way i loose too mutch from my Z axis. Mayby its better to place the Z on the second table at the motor hight.

I'f made a test plate from wood, need to change some things on it but the drawing works! I think i will make the build first from mdf wood so that i can change some things that dont work. I also broke one end mill... didnt look good but we go on

I need to change the width and depth of the linear guide cars for the rest is it all thankfully oke! Need to keep my mind with the milling!

Drawed the second plate today, mayby i mill it tomorrow. I first need to check if the sizes are all correct before i will mill in aluminium. A plate with this size 400x160x20mm costs around 25 euro's (+/- 30 AUD). So i first try it in wood. This is 100 times cheaper. And i can directly check if i done all my measurements correct. On the second plate i can fasten my linear guide cars, z-spindle and for future mount my linear encoder.

Oke! Please tell me if i need to make changes or if i dont see something an you are! Help is always needed! :- ) Ask Questions!?

I'd mill the plate and added it to the construction, now it is waiting on my Nema 34 motor... Adding a another 3.5Kg to the machine :- ) I also need to mill the bottem plate again. The linear guide cant go through... And had some trouble with the spindle mount. I have made it a bit larger dan i have drawed... it fits now and i have changed directly my drawing. Hope the motor will come next week. If thats all oke i can begin with the first 4 plates milling out of aluminium or i first go on with wood.